Posted by rocksea on 07 Aug 2016
There are about 54 species of hornbills in the world, out of which 9 occur in India. The hornbill pictured here is the Indian Grey Hornbill, which is common across the Indian subcontinent, except the wettest (Western Ghats and northeast) and the driest (northwest) parts of the country.
Hornbills have unique breeding habits, where the female confines herself into a nest cavity in a tree, with only a narrow opening through which the male shares the food throughout the nesting period. For the Indian grey hornbills, the total nesting period is about 87 days, where the female is confined to the nest cavity for an average of 76 days. Most of the grey hornbill nests are in hollows of the Mahagony tree family, located nearby riverine habitats. Deforestation, agriculture and other developmental activities have restricted the range of many species like these hornbills.
Grey hornbills as seed dispersers
Hornbills play a key role in seed dissemination, germination and regeneration of trees. This is because they are mainly frugivores (fruit consuming) and can break up/swallow large fruits, and regurgitate the seeds without damaging, making them the perfect dispersers. Since they travel long distances in search of fruits, they are capable of moving these seeds to distant locations.
Grey hornbills are effective seed dispersers for trees such as Premna tomentosa (a teak like tree), Putranjiva, Fern trees and even Sandalwood trees! Many of these are medicinally and commercially valuable trees but they generate very few seeds and propagation depends on birds like these hornbills.
Mid-air play and fight
Like many other hornbills, the grey hornbill has a long curved bill, which has a casque (helmet) on the top. The male hornbills engage in midair clashes where they jar against each other’s casques to establish their dominance and as part of their social play. This behaviour is known as aerial jousting.